CLARKEY

Ive read on here recently that ford add an additive to the diff to stop clunkying etc.Im out of my warranty now and would just like to know what its called ,how much to put in ,do i have to change the oil beforehand etc.If youd be so kind it would be appreciated thanks

TopGhia

It's called Lubrizol. Don't know how much. Ring up Ford spare parts, they'd know. How many k's have you done? Usually diff oil is good for 100,000k's (depending on how the car is treated). You can add that stuff at any time, but changing diff oil is easy, so you may as well change it out if you want to. Make sure you put the right stuff back in - diff oils ain't diff oils.

cheers

'92BigBronco

As far as I know, the additive is only required for models equipped with Ford's "Traction Lock" rearend. The posi unit needs a friction modifier to be added to the differential fluid to prevent it from foaming up as well as to eliminate any of the shudder sometimes associated with a posi unit.

__________________
1992 Ford Bronco
351W
E4OD- B&M Stage 2 shift kit
Full 3" stainless Bassani Exhaust
32" BFG's/stock suspension

"No replacement for displacement."

"Our lugnuts require more torque than most Honda's produce!"

CLARKEY

I got 50,000 on it now .I got a au2 xl ute .I just got a bit of clunking when going from p to r and to drive.Also its quite high pitched noise ,you know the whine they make .I think thats normal though isnt it?Also around the diff there was like a thick grease just sitting on the bottom of it ,so i cleaned it off.I did check the fluid and it was a little foamy.It was just below the hole where the nut goes.Is lubrizol a friction modifier ?How much do i put in and how do u get the old oil out?And what diff oil is the best to put in top ghia?I dont think its a lsd diff well im pretty sure it isnt .THANKS ALOT GUYS

TopGhia

If its an LSD/V8 it will have a metal tag on one of the bolts.

You drain it by taking out the bottom bolt on the diff cover. The owner's manual should tell you what sort of oil to use. A 6 cyl conventional takes a SAE 90 Hypoid, about 1.6 litres. You can use some Nulon G70 as well, if you can't find the Lubrizol.

I would also get a second opinion on the clunking when selecting the gears, it could be the gearbox - auto or manual. If it an auto, check the fluid level and colour.

cheers

CLARKEY

ok thanks mate